Hot-blast stoves



May 8, 1962 Filed March 2, 1959 A. HEUER HOT-BLAST STOVES 2 Sheets-Sheet 1 INVENTOR. Arthur Heuer BY Wmduo f, {M v M A/fornep May 8, 1962 A. HEUER 3,033,544

HOT-BLAST STOVES Filed March 2, 1959 2 Sheets-Sheet 2 FIG 6 I 78 INVENTOR 28 Arthur Heuer AT TORN E Y3 United States Patent 3,033,544 HGT-BLAST STQVES Arthur Heuer, Wieshaden, Germany, assignor to Didier-Werke A.G., Wieshaden, Germany Filed Mar. 2, 1959, Ser. No. 796,341 Claims priority, application Germany Mar. 12, 1958 6 Claims. (1. 263-19) The present invention relates to hot blast stoves particularly of the Cowper type wherein the combustion chamber which serves at the same time as a draft for the air or gas being heated in the heating shaft is located outside of the heating casing. In this type of construction the two casings which are cylindrical in cross-section are each covered with its own cupola and the connetion between the two cupolas is formed by channel shaped conduits which entered the brickwork of each cupola.

When the combustion chamber is positioned outside of the heating casing in its own casing there are some constructional and operational advantages for the shaftlike parts of the heater. However, difficulties arise in efficiently transferring the air or gases from one shaft to the other. In order to remove any damming efiects or turbulences and secure an even uniform distribution of the inflowing air or gases into a shaft it is desirable to provide guiding means for the transfer of the air or gas stream from one shaft to the other.

An object of the present invention therefore is to provide a construction with an eflicient and smooth transfer of the air or gas stream together with the constructional advantages wherein two shafts are utilized.

A still further object of the invention is to provide a construction comprising two shafts with a common cupolalike covering hood extending over both chambers wherein the vault portion of each chamber is open towards the neighboring chamber and a brickwork part is arranged in a tangential plane to both vaults which closes the free space existing between the vaults of each chamber.

With the above and other objects in view which will become apparent from the detailed description below one form of the invention is shown in the drawings in which:

FIGURE 1 is a vertical sectional view through a towerlike wind heater wherein the shafts are located side by side.

FIGURE 2 is a cross-sectional view taken upon section line 2--2 of FIGURE 1 looking in the direction of the arrows.

FIGURE 3 is a similar view taken upon section line 33 of FIGURE 1 looking in the direction of the arrows,

FIGURE 4 is a similar cross-sectional view taken upon section line 4-4 of FIGURE 1 looking in the direction of the arrows.

FIGURE 5 is a cross-sectional view similar to FIGURE 3 of a modified construction wherein both chambers are circular in cross-section with a fiat chord section adjacent one another.

FIGURE 6 is a similar cross-sectional view of a further modification wherein the heater chamber is of circular cross-section while the combustion chamber is of crescent shaped cross-section.

FIGURE 7 is a similar view illustrating a construction of a further modification where the heater chamber is oval shaped and the burner chamber is are shaped in cross-section so that the adjacent portions of the shafts extend along an arc, and

FIGURE 8 is a similar view showing a further modification wherein both shafts are of oval cross-section with their adjacent portions extending along chords.

In constructions of the Cowper type, the spacing of the two chambers from one another may be as large as desired.

Preferably, however, both chambers are arranged adjacent one another as shown in the drawings. The free space between the two cupolas of the two chambers is closed by brickwork in a plane tangential to the cylindrical chambers and is closed by a plane portion of brickwork located at or closely adjacent the top of the two shafts. A common covering hood is provided thereby for both shafts wherein a tangential portion connects the vault of the other chamber so that a rerouting is facilitated corresponding to the cross-section of the respective shaft of the air or gas stream which is leaving or entering the shafts. By means of the tangentially arranged connection in the covering hood between the vault or dome portions of each shaft there is secured an advantageous construction which prevents a stoppage in the flow and minimizes turbulences due to its step-free transfer from one crosssection of one shaft to the other.

The special form of the common covering hood provided by the present invention for the air and gas stream in both flowing directions provides a guidance for the expansion of the air and gas stream over the entire inlet or cross-sectional plane of the shafts. Furthermore the self contained unitary construction forming the brickwork of the covering hood facilitates the compensation of thermal stresses in the hood which occur unilaterally according to the hot air or gas streams.

When the shafts terminate at the same height or nearly at the same height at the top the covering hood at its base may be positioned horizontally. However, in the case of uneven heights the hood may be inclined towards one or the other shaft thereby permitting the rerouting of the air and gas and the distribution of the amounts of flow to the cross section of the shaft. As is known in the Cowper type of construction the cupolas are supported on the metal casings of the two shafts. In this way the brickwork of the two shafts remain unloaded and can therefore yield in response to all thermal expansions particularly in the vertical direction.

Furthermore, instead of the shafts being circular in cross-section and located adjacent one another in more or less linear contact the cross sections of the shafts may be arranged for a fundamentally circular or oval shaped cross section by the construction of a limiting surface as a circular chord having straight parallel surfaces, or for complete circular heater shaft cross sections and a combustion chamber having a sickle like cross section by the construction of curved parallel limiting surfaces standing next to one another.

Referring to the drawings, a heater shaft is indicated at 1 and a combustion chamber at 2 and both of these elements have a circular cross section which are positioned as separate constructions located side by side. The

heater shaft 1 is provided with a metallic casing 3 and the combustion shaft has a metallic casing '5. The casing 3 encircles the brickwork proper 4 of the heater shaft and the casing 3 encircles brickwork 4 of the combustion shaft.

The heater shaft 1 is provided at its lower end with an opening 5 for the exist of the preheating gases or the inlet for the elements such as air, gas or vapor which is to be preheated. The combustion chamber 2 is provided with an opening 6 for the supply of fuel and an opening 7 for the discharge of the elements heated in the heater shaft.

In the heater shaft 1 there is located a grate which supports the lattice work or hollow bricks 16 providing a plurality of vertical channels.

Both shafts are covered with a common hood 8 which comprises the vault portion 9 over the heater shaft 1, the vault portion 9 over the combustion shaft 2 and the brickwork 10 which extends between the vault portions 9 and 9 in a tangential plane thereby closing the free space between such vault portions.

The weight of the hood 8 is supported by its brickwork by means of bracket pins ll and on the metal casings 3 and 3' of the shafts 1 and 2 while allowing a space 17 for the vertical expansion particularly of brickwork 4 and A sand box 14 is provided for the joint between the metal casing is for the hood 3 and the metal casings 3 and 3'. In order to avoid a stoppage in the fiow when introducing agents into the respective neighboring shaft, the agents flowing along the interior plane of the cnpola are rerouted towards the shaft by means of the guiding surface 19 of brickwork which partially or completely covers the stove.

The space which is between the two shafts 1 and 2 within the tangential plane of the brickwork is closed by a covering brickwork 12 of the two cupolas which rests on the metal support provided for sand box 14 carried by the bracket pins 11 and which is located in a plane at the top coinciding with the upper plane of the brickwork of both shafts. The space between the two cupolas is closed by the vault portion 8 which merges with the open edges of the cupolas.

As shown in FIGURE 1 the elements 4, 4, 9, 9' and 10 form a duct of brickwork which is the transfer passage.

As shown in FIGURE 5 when both the heating chamberand the combustion chamber have a substantially circular cross-section these chambers may be positioned closer to one another by providing a chord portion upon each chamber which are positioned adjacent one another. In this FIGURE the reference characters refer. to like parts in FIGURE 1 but with the suffix sub 5.

As shown in FIGURE 6, when both chambers are of a circular cross-section one of the chambers as for instance the combustion chamber, may be provided with an arc portion which is concentric to the: heater chamber. In this figure the reference characters refer to the like parts in FEGURE 1 but with the sufiix. sub 6.

in FEGURE 7 a. construction is shown wherein both chambers have an oval cross-section but are positioned close to one another by preserving the oval shaped crosssection of the heater. chamber and adapting the burner chamber cross-section by means of an arc portion concentrically with the heater chamber. In this figure the reference characters correspond to like parts in FIGURE 1 but are provided with the sufiix sub 7.

FIGURE 8 shows a cross-sectional construction wherein both chambers are of oval shape but the adjacent wall portions thereof are constructed in theform of a chord. In thisfigure the reference characters refer to like parts in FIGURE 1. but are provided with thesnffix sub 8.

It is thought that the invention and its advantages will be understood from the foregoing description and it is apparent that various changes may be made in the form,

construction and arrangement of the parts without departing from the spirit and scope of the invention or sacridoing its material advantages, the form hereinbefore described and illustrated in the drawings being merely a preferred embodiment thereof.

I claim:

1. A tower-like regenerative air or gas heater comprising a brickwork forming aheating shaft, a metal casing enclosing said brickwork, a brickwork forming a combustion shaft arranged outside said heating shaft, a metal casing enclosing the brickwork of said combustion shaft, said shafts being in spaced side by side parallel relation with the upper ends thereof lying in a common horizontal plane, and the brickwork at said'upper ends being arranged to seal the space between said shafts, said shafts having a common covering hood comprising brickwork having dome-shaped portions respectively overlying said shafts, each of said portions having radial dimensions approximately corresponding to those of its associated shaft, each of said portions being open towards the neighboring shaft, an intermediate portion connecting both said first named portionsat the open sides thereof and merging smoothly with the brickwork of said portions and a metal casing enclosing said common covering hood.

2. A heater asset forth in claim 1 wherein said covering hood is supported on said metal casings provided for said shafts.

3. A heater as set forth in claimv 1 wherein, said two shafts are substantially circular in cross-section and each has a fiat chord section positioned adjacent one another.

4. A heater as set forth in claim 1 whereinthe brickwork of said heating shaft is of circular cross-section and the brickwork of said combustion chamber shaft is crescent shaped so that the adjacent portions of. said Shafts extend along an are shaped surface.

5. A heater as set forth in claim 1 wherein the casings of said two shafts are positioned side by side in contact and have oval shaped cross sections each having a fiat chord section located adjacent one another.

6. A heater as set forthrin claim 1 wherein the casings of said two shafts are positioned side by side in contact, one of said casings being oval in cross-section and the 7 other crescent shaped in cross-sectionv so that adjacent portions of said casings extend along an arc.

References Cited in the file of this patent UNITED STATES PATENTS 660,037 Vorbach Oct. 16, 1900 670,260 Waterman Mar. 19, 1901 2,049,815 McGee Aug. 4, 1936 2,141,036 Daniels Dec. 20, 1938 2,175,611 Linder Oct. 10, 1939 2,478,293 MacDonald Aug. 9, 1949 

